Camera



P. FROST April 7, 1936.

CAMERA Filed NOV. 6, 1934 in vemor:

Patented Apr. 7, 1936 UNITED STATES CAMERA Paul Frost, Munich-=Neuharlaching, Germany, assignor to Agfa Ansco Corporation, Bingham= ton, N. Y., a corporation of New York Application November 6, 1934, Serlai No. 751,777

. In Germany November 10, 1933 4 Claims. (Clv 95-31) f This invention relates to a photographic cam era and more particularly to a roll film camera. One of its objects is to provide a roll film carn= era. with a film-transport mechanism which is 5 coupled with the shutter. Another object is such a device which is simple in construction and efli= cient. Further objects will be seen from the de= tailed specification following hereafter.

Reference is made to the accompanying draw= iu ing in which:

Fig.1 represents a longitudinal section of a box camera provided with a shutter which is coupled with the film-transport mechanism, and

Fig. 2 is a rear view of the camera after re= l5 moval of the lid.

According to my invention the tension spring of the shutter is connected with .the film-transport mechanism and preferably consists of a helical spring. A simple circular slider serves as the shutter. In order to avoid an excess strain on the shutter-spring, a friction coupling is inserted between the winding-up coil and the spring, which is adjusted in such a manner, that the helical spring is engaged by the film key only until the as spring of. the shutter-is sufllciently tensioned.

Instead of this sliding coupling, it is also possible to use a constant'gear ratio which corresponds to the height of an image, -'or the film may tension the spring of the shutter while being ad- 30 vanced by the height of one image.

The advantages of this new shutter reside in the fact, that the shutter disk, which is provided with an aperture, does not carry out a pendulum movement, as has hitherto been generally usual,

35 but is always moved in the same direction. This is of importance inasmuch as with pendulous shutter disks, a wire or a time releaser can be employed only with difficulties and if such a releaser shall be used, a special masking device must 4 be provided for the return movement of the circular slider. A shutter provided with a disk turning in one direction, however, is more efficient, and more snap-shot exposures can be made therewith by regulating the power of friction and the 45 more or less great tension of the shutter spring, or by,inserting before the shutter disk a second masking disk by means of which the dimension of the lens aperture and the time of exposure may be adjusted.

50 The shutter disk 3 is mounted in the intermediate wall I of the box camera 2 and is provided with a kidney shaped aperture 4. The flange 1a of the helical spring 1 is connected with the rearof the helical spring '5 also is provided with a flange 8 which by means of a friction spring H is pressed against a disk 9 driven by a toothed wheel. The toothed wheel I0 engages the toothed wheel 12 which is driven by the film key I3. The 5 portion of the film key which engages the film spool, is designated with numeral 54, and the locking means is designated with numeral l5.

In embodiment shown in the accompanying drawing to which the invention is, however, not 1 limited, only one velocity of shutter movement is provided for. 'The shutter disk 3 is maintained in the tensioned state by the arm iii of the release lever it. A stop pin I8 is attached to the shutter disk. The arm 69 of the release lever H is pref- 1., erably mounted in an elastic manner, in order to catch shutter disk 3 after passing the aperture t before the lens Zll.

The apparatus is actuated in the following manner: 21

After inserting the film spools, the winding-up spool is turned until number 1 appears in the number window. In this case, the spring I of the shutter is tensioned, since the turning movement of the film key is transmitted to the tension 25 spring of the shutter by means of the toothed wheels l2, l0 and the coupling 8, 9, H. As soon as the spring is sufllciently tensioned, the coupling 8, 9, ll begins to slide. It is of course possible to construct the friction coupling 8, 9, ll in an adjustable manner in order to tension thereby the spring 1 to a more or less great extent and thereby to vary the shutter speed. The same effect may also be attained by varying the aper ture I.

What I claim is: 1. In a photographic camera in combination, a casing, means for advancing. a light-sensitive material after each exposure, a shutter mounted in said casing, a helical spring for tensioning said shutter, means for coupling said helical spring with said means for advancing said light-sensi- 1'- tive material, and means for tensioning said helical spring to a predetermined amount.

2. In a photographic camera in combination, a casing, means for advancing a light-sensitive material after each exposure, a shutter consisting of a rotatable disk provided with an aperture,

I mounted in said casing, a helical spring for tensioning said shutter, means for coupling said helical spring with said means for advancing said light-sensitive material, and means for tension- .ing said helical spring to a predetermined amount. I

3. In a photographic 'camera in combination, 5

a casing, means for advancing a light-sensitive material after each exposure, a shutter mounted in said casing, a helical spring for tensioning said shutter, means for resiliently coupling said helical spring with said means for advancing said light-sensitive material, and means for tensioning said helical spring to a predetermined amount.

4. In a photographic camera in combination, a casing, means for advancing a light-sensitive material after each exposure, a shutter consisting of a rotatable disk provided with an aperture, mounted in said casing, a helical spring for tensioning' said shutter, means for resiliently coupling said helical spring with said means for advancing said light-sensitive material, and means for tensioning said helical spring to a predetermined amount.

PAUL FROST. 

